Clonazepam

Anticonvulsant for the drug treatment of cerebral seizures from the benzodiazepine group. Clonazepam is used for all forms of epilepsy, including childhood epilepsy.

Clonazepam is rapidly absorbed after oral administration. Maximum blood concentration is reached after 2-3 hours. Excretion takes place mainly unchanged via the kidneys, sometimes also via the stool. A small part is chemically converted and only then excreted. The plasma half-life is about 30-40 hours. The proportion bound to the protein molecules in the blood (plasma protein binding) is 83-87 %, the bioavailability is 71-76 %. It acts via the increased inhibition of GABAergic nerve cells and binds to the GABAA receptor.

Clonazepam is also approved as an antiepileptic drug for children. Clonazepam is also used to treat REM sleep behavior disorder (syn.: "REM sleep behavior disorder" (RBD) or "Schenck syndrome"). Taken before bedtime, it reduces muscle activity in REM sleep.

Clonazepam is also effective as an alternative medication for restless legs syndrome. It is also used in many countries as an anxiolytic as a first-line treatment for panic attacks. Other areas of application include drug monitoring of inpatient alcohol withdrawal and the rare congenital hyperecplexia.

Off Label Use: Glossodynia and Stomatodynia: also as local application (3 × 1.0 mg/day; sucking of a clonazepam 1 mg, sucking tablet for 3 minutes, then spitting it out, 3 times daily for 14 days). The authors suspect a local effect of clonazepam - beyond the placebo effect - on the benzodiazepine-GABA-A receptor complex in the nerve endings of the lingual mucosa.

Use during pregnancy and lactation: Use during pregnancy only if urgently indicated.

Corresponding to the spasm suppression, clonazepam has a general attenuating effect on the central nervous system, so that fatigue, drowsiness, dullness, reduced muscle tone, muscle weakness, dizziness, lightheadedness, balance problems and prolonged reaction time may occur. With long-term therapy, these side effects usually decrease due to a habituation effect. They can be partly avoided by a creeping start of treatment.

Other more frequent side effects on the central nervous system are concentration disorders, restlessness, confusion and memory disorders, which can also be associated with inappropriate behaviour.

As paradoxical reactions, excitability, irritability, aggressive behaviour, nervousness, hostility, anxiety, sleep disorders, nightmares and vivid dreams have been observed. Rarely, allergic symptoms such as urticaria, itching, rashes, swelling of the face and oral mucosa and larynx occur.

Rare are transient effluvium, pigmentary shifts, nausea and upper abdominal discomfort, headache, chest pain, thrombocytopenia, libido disorder, impotence and urinary incontinence.

In individual cases, clonazepam can also attenuate the respiratory centre and lead to reduced respiratory drive. In infants and small children, there may also be increased salivation and mucus production in the airways with breathing difficulties.

Rivotril (D, CH), Antelepsin (D), and generic drugs sold under the substance name.

Dependence potential: Clonazepam, like all benzodiazepines, can lead to physical and psychological dependence with withdrawal symptoms.